What are the harmful effects of photochemical smog and how can they be controlled?

Explanation

Photochemical smog can be controlled in the given ways: 1 By using efficient catalytic converters in the automobiles which will check the release of both `NO_(2))` and certain hydrocarbons known as primary precursors. This will automatically check the formation of secondary precursors. Such as Ozone and PAN. 2 By spraying certain compounds into the atmosphere which will control hydrocarbons, `NO_(2)` , PAN. 3 Certain plants like pinus, pyrus, vitis quercus etc., are capable of causing the metabolism of the oxides of nitrogen. Hence their plantation could be helpful.